@charset "utf-8";

/* =========================================================
   Modernized theme for the existing XHTML layout
   - Keep HTML unchanged
   - Lighter background, card container, softer sidebar
   - Better typography & spacing
   ========================================================= */

/* ----- Base / Variables ----- */
:root{
  --bg: #eef2f5;
  --card: #ffffff;
  --text: #1f2933;
  --muted: #52606d;

  --accent: #0ea5a4;         /* teal accent (safe + modern) */
  --accent-2: #2c7be5;       /* optional blue */
  --border: rgba(31,41,51,0.12);

  --sidebar: #f1f3f5;
  --nav-bg: #e9ecef;
  --nav-hover: #17184b;

  --radius: 10px;
  --shadow: 0 6px 24px rgba(0,0,0,0.10);
}

/* ----- Page ----- */
html, body{
  height: 100%;
}

body{
  font: 16px/1.75 "Hiragino Kaku Gothic Pro", "Yu Gothic", Meiryo, Osaka, Roboto, system-ui, -apple-system, "Segoe UI", sans-serif;
  background: var(--bg);
  margin: 0;
  padding: 0;
  color: var(--text);
}

/* Remove default list spacing quirks */
ul, ol, dl{
  padding: 0;
  margin: 0;
}

a img{
  border: none;
}

/* Links */
a:link{
  color: var(--accent-2);
  text-decoration: none;
}
a:visited{
  color: #476fbe;
  text-decoration: none;
}
a:hover, a:active, a:focus{
  text-decoration: underline;
  outline: none;
}

/* Headings / paragraphs spacing (existing HTML uses h2 + h3 heavily) */
h1, h2, h4, h5, h6, p{
  margin-top: 0;
  padding-right: 0;
  padding-left: 0;
}
h3{
  margin-top: 26px;
  margin-bottom: 10px;
  padding-right: 0;
  padding-left: 0;
}

/* ----- Container as a centered “card” ----- */
.container{
  width: 1000px;          /* keeps your current layout */
  max-width: calc(100% - 32px);
  background: var(--card);
  margin: 28px auto;
  overflow: hidden;
  border-radius: var(--radius);
  box-shadow: var(--shadow);
}

/* ----- Header ----- */
/* ===== Header base ===== */
.header{
  position: relative;
  min-height: unset; /* ロゴが確実に収まる高さ */
  padding: 14px 20px 18px 20px;
  background: linear-gradient(90deg,
    rgba(14,165,164,0.18),
    rgba(44,123,229,0.10)
  );
  border-bottom: 1px solid rgba(31,41,51,0.12);
}

/* ===== Common logo style ===== */
.site-logo{
  position: absolute;
  top: 15px;
  height: 90px;      /* 基本サイズ */
  width: auto;
  z-index: 50;       /* slideshow より前面 */
}

/* 左上（JPEG） */
.logo-left{
    top: 25px;
    height: 80px;
    left: 300px;
}

/* 右上（PNG） */
.logo-right{
    top: 15px;
    height: 100px;
    right: 300px;
}

.event-date{
  text-align: right;
  font-size: 18px;
  color: #334155;
  margin-top: 12px;
}

/* ===== Slideshow stays below logos ===== */
#slideshow{
  position: relative;
  z-index: 1;
  margin-top: 10px;
}

/* ===== Responsive (optional) ===== */
@media (max-width: 768px){
  .site-logo{
    height: 52px;
    top: 10px;
  }
}

/* ----- Layout columns ----- */
.sidebar1{
  float: left;
  width: 170px;
  background: transparent;
  overflow: hidden;
  height: auto;                /* IMPORTANT: remove fixed height */
  padding: 14px 10px 18px 10px;
  border-right: 1px solid var(--border);
}

.content{
  float: left;
  width: calc(100% - 170px);
  padding: 22px 26px 28px 26px;
  background: var(--card);
  box-sizing: border-box;
}

/* Old helper class in your HTML */
.maintxt{
  margin-top: 0;
  padding-right: 0;
  padding-left: 0;
  color: var(--text);
}
.maintxt p{
  color: var(--text);
}

/* Content lists */
.content ul, .content ol{
  padding: 0 0 0 22px;
  margin: 8px 0 18px 0;
}
.content li{
  margin: 6px 0;
}

/* ----- Title area styling ----- */
.content h2{
  font-size: 30px;
  line-height: 1.25;
  margin: 0 0 14px 0;
  padding: 14px 16px;
  border-radius: 8px;
  background: rgba(14,165,164,0.12);
  border: 1px solid rgba(14,165,164,0.20);
}

.content h3{
  font-size: 20px;
  margin-top: 22px;
  padding: 0 0 8px 0;
  border-bottom: 2px solid rgba(31,41,51,0.10);
}

/* Red notice line in your HTML uses <font color="red">... */
.content font[color="red"]{
  color: #b91c1c !important;
  font-weight: 700;
}

/* ----- Navigation ----- */
ul.nav{
  list-style: none;
  margin: 0;
  padding: 0;
}

ul.nav li{
  border: none;
  margin: 0 0 10px 0;
}

/* Button-like nav links */
ul.nav a, ul.nav a:visited{
  display: block;
  width: auto;
  text-decoration: none;
  background: var(--nav-bg);
  color: var(--text);
  padding: 10px 12px;
  border-radius: 8px;
  border: 1px solid rgba(31,41,51,0.10);
  transition: transform 0.12s ease, background 0.15s ease, color 0.15s ease, box-shadow 0.15s ease;
}

ul.nav a:hover, ul.nav a:active, ul.nav a:focus{
  background: var(--nav-hover);
  color: #fff;
  text-decoration: none;
  box-shadow: 0 6px 16px rgba(23,24,75,0.18);
  transform: translateY(-1px);
}

/* ----- Footer ----- */
.footer{
  padding: 14px 26px;
  background: #f3f5f7;
  position: relative;
  clear: both;
  border-top: 1px solid var(--border);
  color: var(--muted);
  font-size: 14px;
}

/* Float helpers (keep) */
.fltrt{ float: right; margin-left: 8px; }
.fltlft{ float: left; margin-right: 8px; }
.clearfloat{ clear: both; height: 0; font-size: 1px; line-height: 0; }

/* ----- Slideshow (keep your JS behavior) ----- */
/* Your HTML shows slideshow images are 1000px wide; make it responsive */
#slideshow{
  position: relative;
  width: 100%;
  height: 100px;
  margin: 0;
}

#slideshow div{
  position: absolute;
  top: 0;
  left: 0;
  z-index: 8;
  opacity: 0.0;
  margin: 0;
  background-color: transparent;
  height: 100px;
}

#slideshow div.active{
  z-index: 10;
  opacity: 1.0;
}

#slideshow div.last-active{
  z-index: 9;
}

#slideshow div img{
  width: 100%;
  height: 300px;
  display: block;
  border: 0;
  margin: 0;
  object-fit: cover;
  border-top-left-radius: var(--radius);
  border-top-right-radius: var(--radius);
}

/* ----- Responsive tweak ----- */
@media (max-width: 820px){
  .container{
    width: auto;
    margin: 14px auto;
    border-radius: 12px;
  }
  .sidebar1{
    float: none;
    width: auto;
    border-right: none;
    border-bottom: 1px solid var(--border);
  }
  .content{
    float: none;
    width: auto;
    padding: 18px 18px 22px 18px;
  }
  #slideshow, #slideshow div, #slideshow div img{
    height: 220px;
  }
}

/* ----- Print (optional but helpful for programs) ----- */
@media print{
  body{ background: #fff; }
  .container{ box-shadow: none; margin: 0; border-radius: 0; }
  .sidebar1{ display: none; }
  .content{ width: 100%; float: none; }
  #slideshow{ display: none; }
}
/* ---- FIX: float drop & huge blank space in sidebar ---- */
*, *::before, *::after { box-sizing: border-box; }

/* sidebar width includes padding now */
.sidebar1{
  width: 170px;           /* このままでOK */
  padding: 14px 10px 18px 10px;
}

/* content really becomes "100% - sidebar" */
.content{
  width: calc(100% - 170px);
}

/* remove the artificial vertical spacer <p>　</p> in sidebar */
.sidebar1 p{
  margin: 0;
  padding: 0;
  line-height: 0;
  height: 0;
}